i ended up sending mine to the admissions committee except for tulane's, which i addressed to dr. pisano. i started out trying to find the names of deans, etc... but then i didn't know if i should send it to the dean of admissions or the director of admissions and didn't know if the name in msar was outdated b/c i couldn't find the person on the web, etc... to make things easier, i settled on using admissions committee for the address and "dear sir or madam" as the greeting.
i did a search on this a couple of weeks ago. there are a couple of threads from last year that discuss this issue. one was started by doctora foxy i believe.